Preheat the grill. Preheat the oven to 200 degrees F.
Grill the beef on each side just until charred.
In a small bowl combine the garlic, pepper, salt, thyme and Worcestershire. Rub the beef with the spice blend.
Place the beef in a hotel plan and cook until the internal temperature reaches 120 to 130 degrees F, 2 hours, reserving the pan drippings for the au jus.
In a small saucepan, heat the pan drippings with 1/2 teaspoon cornstarch, adding more cornstarch, 1/2 teaspoon at a time, until the sauce reaches desired consistency.
Slice the beef into 10-ounce portions and serve with the au jus.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.